Dr John Schofield, of the Department of Archaeology at the University of York, said they are worthy of being preserved as heritage pieces and should be preserved despite being offensive and rude.

The markings discovered on the walls of the flat the group rented in London in the mid-1970s lend themselves to archaeological investigation as much as drawings made by early humans in the caves of Lascaux in southern France, he insists.

It was even suggested that the intact Pistols graffiti - found behind cupboards in the property in Denmark Street, central London - may be of greater significance than the discovery of early Beatles recordings and is "a direct and powerful representation of a radical and dramatic movement of rebellion."

Researchers carried out a detailed analysis of the graffiti's content and cultural significance, concluding that while it could be considered rude, offensive and uncomfortable, its presence confirms the flat as an important historical and archaeological site.

The drawings lie in the upper room of a two-storey 19th century property now used as offices in the famous street known in the 60s as Tin Pan Alley.

The bulk of them are by John Lydon, or Johnny Rotten, and consist of eight cartoons depicting himself and other members of the band, as well as their manager, Malcom McLaren, and other Pistols' associates.

Researchers are deciding whether or not the property should become a conventional heritage site with a blue plaque to mark its historical significance.

Dr Schofield said: "So could Denmark Street be Punk's Lascaux?

"The tabloid press once claimed that early Beatles recordings discovered at the BBC were the most important archaeological find since Tutankhamun's tomb.